import http

from bs4 import BeautifulSoup, ResultSet, Tag

import requests

resp = requests.get("http://www.nmc.gov.cn/publish/forecast/ABJ/bei-jing.html")
resp.encoding = 'utf8'
html = resp.text

soup = BeautifulSoup(html, 'lxml')

tag: Tag = soup.find_all(id='forecast')[0]

results = BeautifulSoup(tag.text, 'lxml')

rs: ResultSet = results.find_all(class_="day")
print(rs)